A vinylidene fluoride-based polymer resin is a fluorine-based resin which is excellent in mechanical properties, weather resistance, chemical resistance, electrochemical stability, flame resistance, etc., and is widely used in various industries such as for paints, electronic products, films, and separation membranes.
The vinylidene fluoride-based polymer resin is a semi-crystalline polymer resin composed of a crystalline region and an amorphous region, and in particular, the degree of crystallization of the semi-crystalline polymer resin affects overall physical properties and characteristics thereof.
Generally, it is known that as the degree of crystallization of a semi-crystalline polymer resin increases, the mechanical strength, heat resistance, and chemical resistance or the like are improved.
Recently, in this technical field, there has been an increasing demand for a technique for manufacturing polyvinylidene resin compositions and molded products having excellent strength and chemical resistance in an efficient manner.
For example, Korean Patent Laid-open Publication No. 2013-0110848 discloses a method of improving crystallinity through multi-stage heat treatment processing such as heating, cooling, and sintering in order to obtain a highly crystalline polyvinylidene resin, and there is a detriment in that it takes a lot of time to complete the final manufacturing.
In addition, Korean Patent Laid-open Publication No. 10-2013-0016153 discloses a method of manufacturing a high strength hollow fiber membrane by improving the crystallinity of a polyvinylidene resin through a stretching process, but in the manufacturing method of such a hollow fiber membrane, a heat treatment step for obtaining sufficient crystallinity at the stage before stretching is essential.
Therefore, there is a need to develop a method capable of providing a polyvinylidene resin composition and a molded product having excellent physical properties through simplified processes and simple methods.